Does anyone know what LEDs an LG 55LM5400 uses?

[Daveleone]

I have an LG 55LM5400 with 5 LEDs out on various strips. I'd prefer to just replace the failed LEDs rather than scrapping all the strips. I found these on eBay (https://www.ebay.com/itm/10x-LEDs-fo...-/312033321746). But does anyone know what the equivalent is at digikey?

Thanks!

[Diah]

its 3528 1W you can buy it from china 100 pieces from the place i bought always and they are perfect tested product

better take out defect one and look of the chassis figure and you can measure it too with mm.

[Daveleone]

Originally Posted by Diah

its 3528 1W you can buy it from china 100 pieces from the place i bought always and they are perfect tested product

better take out defect one and look of the chassis figure and you can measure it too with mm.

Perfect! Thank you. BTW, I noticed that the same seller seems to have the same LEDs, same quantity for less money via this link. https://www.aliexpress.com/item/4001071783495.html
They look exactly the same as the ones you linked above. Do you find any difference? If not, I will probably buy this lot.

Or what do you think about this, from a different seller: https://www.aliexpress.com/item/32950653660.html

Thanks again!

[neilc6]

Typo in your model number. Probably 55LN. I had a 42LN come back 2 years after I replaced just the bad strips with used ones. The new failures were on the original strips (I can tell by the double sided tape I use) and with the backlight turned down to 60% . If you don't want to have future issues, replace all the strips with new. I think the 55LN model uses the 55LB style of strips with the thick lenses. These tend to fall off with age as well and difficult to remove without popping off every lens. If not glued back perfectly centered, they will cause halos and bright spots.

[Daveleone]

Originally Posted by neilc6

Typo in your model number. Probably 55LN.

You are right, I just double checked. 55LN5400. Thanks for the correction, and for the experienced advice. Much appreciated.

[neilc6]

Last time I gave this advice, the OP replied why should he spend money on new strips when it was only a couple of bucks for LED modules. Some of the thick lens LG strips use 6V modules instead of 3V.

[Diah]

Originally Posted by Daveleone

Perfect! Thank you. BTW, I noticed that the same seller seems to have the same LEDs, same quantity for less money via this link. https://www.aliexpress.com/item/4001071783495.html
They look exactly the same as the ones you linked above. Do you find any difference? If not, I will probably buy this lot.

Or what do you think about this, from a different seller: https://www.aliexpress.com/item/32950653660.html

Thanks again!

my link as i have it on my order list before 1 1/2 years.. but the one you linked to same seller. are the same LED ( good catch )

the last link you mentioned.. they are not for TV backlight.. as they dont have built in fw ziner diode.

if this is yours first time to work on direct LED for TV BL. you will have much like high % spot light because of the lens sitting. this why i suggest you to move on with neilc6 advice and find complete ready strips.

[Daveleone]

Originally Posted by Diah

my link as i have it on my order list before 1 1/2 years.. but the one you linked to same seller. are the same LED ( good catch )

the last link you mentioned.. they are not for TV backlight.. as they dont have built in fw ziner diode.

if this is yours first time to work on direct LED for TV BL. you will have much like high % spot light because of the lens sitting. this why i suggest you to move on with neilc6 advice and find complete ready strips.

Got it. It's not my first time working on LED repairs, and I have struggled with lenses in the past, but I have found that if I take care to keep them oriented exactly how I pried them off, then gluing them back becomes fairly easy. That said, I decided I am going to take neilc6's advice just to ensure the longevity of the repair. It's only about a $20 difference and will save me some time, plus will make sure whoever buys the TV will be able to get good use out of it for many years to come.

Thanks to both of you for all of the valuable info!

[abduln21]

Can Anyone help with the leds for the edgelight on an LG 60UH6035 4k tv?

[Daveleone]

Originally Posted by Diah

i suggest you to move on with neilc6 advice and find complete ready strips.

Hi Diah, just a follow up on this. I ordered a complete set of strips from AliExpress. They arrived recently and I installed them in the TV, but they create a bright spot at every LED. (see attached photos). It seems like the diffusers on these strips do not create the same diffusion pattern as those on my original strips.

Do you know if POLA2.0 LED strips (the ones I bought) are supposed to be compatible replacements for LZ5501LGEPWA-DL84 strips (the original strips I'm replacing)? I'm wondering if 1) I bought incompatible strips, and I can sell these and they will work ok for someone else, or 2) the strips I got from the seller are defective and I should throw them away.

Let me know what you think. Thanks!

[Diah]

a compatible item i understand it work... but if there effect we need to know the reason.... if the lens are different then this another story..

did you put the all sheet in order as its?
the first hard( thick) white plate which it cover the leds.. had 2 surfaces.. one smooth and other not... the smooth surface should face the screen and other sheets

[neilc6]

I've had issues with these thick LB style strips with some Chinese vendors. Had shadowing on a 42LB series (substitutes with the square lens style - have used this style before no issues for 32LB) and had them replaced with the original style. They were better but still not as even as the originals. Enclosed pics with bottom row original strips.

The POLA2.0 strips have a slightly smaller lens and for a Heesung panel. I am still looking for reasonably priced 50" strips for a 50LN5310 not realizing there were two different thick lens styles.

Lesson for the these thick lens strips is to try to find originals or use trusted vendors. I would show the vendor your pics and ask for a refund.

[Diah]

so if he changed led unit parts was better than this equal

[Daveleone]

Originally Posted by neilc6

I would show the vendor your pics and ask for a refund.

I actually assumed these strips were defective/poor quality and already went back & forth with the vendor and showed them the photos. They claimed the LED strips were working fine. I escalated to AliExpress, showed them tons of pics, explained what happened, and AliExpress closed the case and refunded me only ~$2. *sigh*

I took a close look at them and it looks like the lenses are mounted a few mm higher off the strip than the originals, which could be the manufacturing defect. If you think these strips are defective and wouldn't work right for someone trying to replace their original POLA2.0 strips, I'll just harvest the LEDs off them and throw the strips away.

Originally Posted by diah

did you put the all sheet in order as its?

Yes, I was very careful to replace all of the sheets in the correct order/orientation.

[Daveleone]

Originally Posted by Diah

did you put the all sheet in order as its?

Originally Posted by neilc6

...

Just to be sure, last night I tested all 3 sheets in every possible combination and no combination resolved the issue. The original way that I had them oriented was definitely the correct way.

I also noticed that in the replacement strips the lenses appear to be mounted a few mm higher off the strip than the lenses on the originals. This would account for the strange/different diffusion pattern.

I'm still not sure if 1) The tighter/brighter diffusion pattern is normal for POLA2.0 strips, and TVs originally designed to use POLA2.0 strips have the right diffusion sheets above it to compensate for this (i.e. they're actually not compatible replacements for LZ5501LGEPWA-DL84, but would work fine for someone replacing POLA2.0 and I can safely sell them as such), or 2) these strips are defective and I should scrap them.

@neilc6 @Diah What do you think?

[Diah]

Originally Posted by Daveleone

What do you think?

POLA2.0 just label had nothing to do with TV brand. its duplicated manufacturing so it should hold different label to avoid any legal issue.

they consider at this duplicated process the amount of LEDs and the distance between each LED beside the working V. and wiring of the string for matching. the issue you may face not at lenses as any other thinking about.. but the LED module had double or 1/2 more Lumen than the one build in. and this related not as dummy from supplier, but the LEDs manufacturing later days became more efficient with Lumen as they was 4-5 years ago.

i am certain sure even if you are going to take out LED unit from yours new strings to replace it with defect one at the ORG string will have same effect even with OLD ORG Lens.

Lumen on LED could be controlled by VA and Freq. i am not sure if you are willing to change your Power Boards LED section design.

[Daveleone]

Originally Posted by Diah

the issue you may face not at lenses as any other thinking about.. but the LED module had double or 1/2 more Lumen than the one build in...i am certain sure even if you are going to take out LED unit from yours new strings to replace it with defect one at the ORG string will have same effect even with OLD ORG Lens.

Thank you for the very detailed reply!

As a test, I decided to pry one of the lenses off of one of the new strips, turn it slightly sideways (so that it would sit a few mm lower) and power the strip. It made no difference. So, the distance of the lens from the strip was not the problem. Then, I took a lens from one of the old strips and put it over the new strip. I've attached a photo (new lens on the left, old lens on the right). The diffusion pattern of the old lens is quite different from that of the new lenses. (One other thing to note is that these LEDs cast a yellow ring whereas the original LEDs cast a white ring. I don't think this will affect the functionality/usability, but it is a notable difference)

In the end, this is a problem with the LENSES. I'm not sure if POLA2.0 lenses are just designed differently and this is normal for POLA2.0 strips (and they are not suitable replacements for 55LN5400), or if the lenses used by this seller are just defective. **What do you think?**

I'll try using the old lenses with the new strips. I think that will work. I will update you when it's done. Thanks again for the help!

[Daveleone]

Originally Posted by Diah

the LED module had double or 1/2 more Lumen than the one build in. I am certain sure even if you are going to take out LED unit from yours new strings to replace it with defect one at the ORG string will have same effect even with OLD ORG Lens.

Well, you were right (of course you were! you are the expert ). Even with the old lenses and wider diffusion pattern, the bright spots were less noticeable, but still noticeable (see the upper right corner of the attached photo). My conclusion is that POLA2.0 are not good replacements for the 55LN5400 set as it doesn't have adequate diffusion layers to diffuse the brighter LEDs evenly across the panel.

I was able to buy a single A-side replacement strip (which is all I needed) that matches my original part number from a seller on eBay for $10. Once I receive that, all should be well.

Thank you very much for your help and guidance throughout this process!

[Diah]

Originally Posted by Daveleone

Well, you were right
Thank you very much for your help and guidance throughout this process!

while you are waiting on yours single A strips. now you have first group added 1 single A from POLA2.0 strings. can you please read the voltage on the LED sockets at power boards your measurement need to be direct on the each group + & - .. let us compare both groups with POLA2.0 & without.

[Daveleone]

Originally Posted by Diah

while you are waiting on yours single A strips. now you have first group added 1 single A from POLA2.0 strings. can you please read the voltage on the LED sockets at power boards your measurement need to be direct on the each group + & - .. let us compare both groups with POLA2.0 & without.

Unfortunately, I've already taken things apart again. Do I need to test the voltage with the TV on? or can I just disconnect the lead and test them out of circuit using my LED tester? I did a quick test with the LED tester.

Bottom 3 strips of LEDS (36 old LEDs) = 98.5v = 2.736v per old LED

Top 4 strips of LEDs:
- 42 old LEDs + 6 new LEDs = 130v.
- Therefore, 6 new LEDs + 42 * 2.736v = 130v
- Therefore, 6 new LEDs = 15.088v
- Or 2.514v per new LED

Hmm... but I just tested a single strip of 6 new LEDs out of circuit and got 15.8v = 2.63v per new LED